1. Field of the Invention
This invention relates to electrical connector assemblies and in particular to a locking feature for affixing the connector assembly, either electrically or mechanically, to a substrate, such as a printed circuit board.
2. Summary of the Prior Art
It is common to incorporate into electrical connector assemblies a board-lock or eyelet in order to anchor the connector assembly to a substrate, such as a printed circuit board. These board-locks may take on a number of different configurations and may be made of various materials, such as a molded plastic extension of the connector housing or a metallic member either an insert or a portion of a shielding housing. In some cases it is desirable to have the option of utilizing the board-lock as a conductor and most typically as a conductor of the ground-path between the shielding associated with the connector assembly and a ground plane established on the substrate. In this case, it is known to form a board-lock insert of a conductive metal and have it electrically engaged with the shielding by such processes as soldering or a interference fit therewith. The board-locks further are received in openings or in the substrate that have conductive surfaces therein, such as plated through holes. The engagement between the conductive surfaces and the board-lock can occur through interference fit or soldering.
As soldering of the board-lock to the conductive surfaces of the opening in the substrate require relatively close tolerances both for positioning and hole size in order that the soldering is effective, additional costs are incurred in the manufacturing process. In order to avoid these additional costs associated with tighter manufacturing tolerances, there have been a number of developments in he area of more tolerance forgiving board-lock configurations. These board-lock configurations typically utilize an interference fit with the conductive surface within the opening where the boar-lock has some inherent resiliency. A example of another type of board-lock is disclose in U.S. 4,865,555. Here, a board-lock for a connector assembly is located in a housing of that assembly. The board-lock includes a positioning portion extending outward from the housing that is received within a substrate and extends therethrough. The board-lock is then compressed such that the portion extending through the substrate deforms in such a way that one connector is fixed to the substrate by the now expanded portion of the board-lock beneath the substrate.
While both these examples and other known examples perform reasonably well, there are a number of improvements that still can be addressed. Some of the components relatively complicated to manufacture and therefore add cost to the connector assembly. Others are not tolerance forgiving as might be desired for some applications. And still others may not effect the desired electrical connection with out damaging the conductive surfaces in the opening of the substrate. Finally, while it is desired to be able to form an electrical connection the board-lock still must be able to effectively mechanically engage the substrate, so it is also desired to assure good mechanical retention. Furthermore, in order to allow for manufacturing of a basic common substrate, whether or not a conductive opening is to be used, it would be desirable for the board-lock to have a wide range of engagement effectiveness so that when the opening is plated, and thereby smaller in diameter, the board-lock will make an effective engagement and if the opening is not plated, and thereby larger, the board-lock still will be able to accommodate this larger diameter.